Actual diameter of 17670 Li-ion batteries

aurgathor

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Does anyone know the actual (measured!) diameter of some 17650 or 17670 Li-ion batteries?

The back story is that I have an older flashlight with a 3.6V NiMH battery pack (16.6 mm x 85.1 mm) that need to be replaced. The battery pack is available as a special order item for around $25 + S/H; however, I think I could get a better battery for less money if I replace it with a Li-on battery. (and a conductive spacer to make up for that roughly 20 mm))

One 17670 battery has the diameter listed as 17 +/- 0.5 mm. However, the inside diameter of the battery compartment is only 17.1 mm, meaning that an 17670 with the above tolerance may or may not fit. That's why I'd like to know if someone has some actual, measured data on it. The backup plan would be the 16650.
 

fivemega

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Does anyone know the actual (measured!) diameter of some 17650 or 17670 Li-ion batteries?
There is no such a thing as "ACTUAL" or "ABSOLUTE" size.
Each company has it's own "tolerance" so mighe be different from one to other brands.
Also if these cells are protected, then each second company who add protection circuit, may have different "tolerance" which added on original size.
And remember no battery is perfectly cylindrical and when you measure one, you may have slightly different number if you turn the cell 45 or 90 degree.
The next problem is thickness of shrink tube each company use.

In your case I will go with 16650
 

ebuchner

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To expand on what everyone mentioned, you'd be lucky to find a 17670 cell with 1800 mAh capacity, but 16650 cells with a capacities of 2500 mAh are readily available. Two birds, one stone. The 17670 is kind of a semi-obsolete cell that manufacturers aren't putting much effort into in this decade.
 

aurgathor

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>> There is no such a thing as "ACTUAL" or "ABSOLUTE" size.

There is such a thing as an "ACTUAL" size: I'm simply looking for measurements of whatever 17670/17650 someone may have. I understand that they may differ between manufacturers and batches -- I'm just curious about actual values.

>> To expand on what everyone mentioned, you'd be lucky to find a 17670 cell with 1800 mAh capacity,

I was looking at these ones before posting: https://www.batteryjunction.com/batteries/shop-by-type-batteries/rechargeable?battery_size=44

The original NiMH battery is speced at 1000 mAh 3.6V; and with a manufacture date of 11/17/2008, most anything should be significantly better than that.
 

ebuchner

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What I can say is that manufacturers very often fudge their sizes towards the upper ends of the specs, and fudge their capacities to the lower ends of the specs. There's a very good chance that the majority of the cells you'd get out of a batch of those ultrafires would probably be just a hair under the maximum diameter of 17.5 mm (probably too big for a 17.1 mm body) with a capacity of 1750 mAh or less. 16650 Keeppower cells from illumn would almost certainly fit even at the upper end of their diameter limits.
 

aurgathor

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I just received two Orma Kurda 16650 batteries -- their actual diameter varies between 16.6 and 16.7 mm.

They work much-much better than the old NiMHs, and at $16 for two, they were cheaper than a *single* replacement NiMH battery pack.
 
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